1. Field of the Invention
This invention relates to a toothbrush and, more particularly, to a toothbrush having a bristle portion molded from an ion eluting-type ceramic. The toothbrush of the present invention is effective in preventing dental caries and pyorrhea.
2. Description of the Prior Art
An ordinary toothbrush consists of a synthetic resin molded into a unitary body that includes a bristle portion having implanted hairs, hereafter referred to as bristles, and a handle portion gripped by the hand. The bristles of the toothbrush are rubbed against surfaces (corona dentis) of the user's teeth to produce friction which acts to remove tartar from the teeth. However, tartar removal requires that the toothbrush be rubbed against the teeth with considerable force. This is a drawback since such intense rubbing wears down the surfaces oi the teeth.
With the advancements that have been made in the field of minature batteries, toothbrushes incorporating such batteries have been developed and attempts have been made to utilize such toothbrushes in removing tartar from the surfaces of teeth by electronic decomposition. Toothbrushes of this kind, ordinarily referred to as electronic toothbrushes, include a battery accommodated within the handle portion, an electrically conductive rod extending to the bristle portion and having one end thereof connected to the battery, and an electrically conductive plate disposed on the surface of the handle portion and connected to the battery. When the user grasps the handle portion of the electronic toothbrush and, hence, contacts the conductive plate, an electric circuit is formed through the user's body, the user's teeth and the conductive rod. As a result, the toothbrush, which exhibits negative polarity, draws tartar of positive polarity from the surface of the teeth, thereby removing the tartar by decomposition.
Though an electronic toothbrush of this type decomposes and removes tartar from a tooth surface, absolutely no consideration is given to strengthening the tooth surface layer (cuticula dentist). In other words, a disadvantage of such an electronic toothbrush is that the tooth surface layer is inevitably worn down by contact with the bristles implanted in the bristle portion.